Concave Lens

Q.

Which type of lens is converging and which type of mirror is converging?

Q.

A lens having two spherical surfaces, both bulging outward is called ______________?

1. plano-concave lens

2. concave lens

3. convex lens

4. plano-convex lens

Q. Himanshu passes a parallel beam of light through a concave lens. He observes that when the ray of light passes through the lens it___________.

1. diverges
2. converges
3. is parallel
4. meets at a point

Q.

A lens which is thinner at its centre than at its edges is called ___.

1. concave lens

2. convex lens

3. plano-concave lens

4. plano-convex lens

Q. A convex lens has a divergent action and a concave lens has a convergent action.

1. True
2. False

Q.

A convex lens is a ________ and a concave lens is a _________.

1. converging lens, diverging lens

2. diverging lens, converging lens

3. converging lens, converging lens

4. diverging lens, diverging lens

Q. Point out difference between a convex lens and a concave lens.

Q.

A lens which is thinner at its centre than at its edges is called ___.

1. concave lens

2. convex lens

3. plano-convex lens

4. plano-concave lens

Q. Choose the correct pair.

a. Centre of curvature	i. Effective diameter of the circular outline of a lens
b. Principal axis	ii. Line joining the centre of curvatures of the two surfaces of a lens
c. Optical centre	iii. Centre of the sphere of which the lens forms a part
d. Aperture	iv. Central point of a lens

1. a - ii, b - iii, c - i, d - iv
2. a - iii, b - ii, c - iv, d - i
3. a - iv, b - ii, c - i, d - iii
4. a - i, b - iii, c - ii, d - iv

Q. Choose which of the following options are correct.

1. 
2. 
3. 
4. 

Q.

Which of these has virtual focus?

1. Concave lens

2. Convex lens

3. Convex mirror

4. Concave mirror

Q. A lens which has two spherical surfaces both bulging inside is called.

1. convex lens
2. plano-convex lens
3. concave lens
4. plano-concave lens

Q. A biconcave symmetric lens is placed inside a medium whose refractive index is $n_{medium}$ with respect to the air. The lens acts as a converging lens (convex lens) in this medium. So what can you say about the refractive index of the lens ($n_{lens}$) with respect to the air?

1. $n_{lens}$ > $n_{medium}$
2. $n_{lens}$ < $n_{medium}$
3. $n_{lens}$ = $n_{medium}$
4. cannot be predicted

Q. Choose which of the following options are correct.

1. 
2. 
3. 
4. 

Q.

Which of the following options are correct?

1. 

2. 

3. 

4. 

Q. The magnification produced by a concave lens is

1. positive always
2. infinity
3. zero
4. negative always

Q. Which of the following option(s) is/are correct?

1. 
2. 
3. 
4. 

Q.

Imagine a concave lens placed in a liquid whose optical density is equal to that of the liquid. What will be the nature of the lens?

1. Diverging

2. Both converging and diverging

3. Converging

4. Neither converging nor diverging

Q. In the diagram below, XX' represents the principal axis, O the optical centre and F the focus of the lens. Complete the path of rays A and B as they emerge out of the lens.

Q.

A lens having two spherical surfaces bulging outward is called ______________.

1. concave lens

2. convex lens

3. plano-convex lens

4. plano-concave lens

Q. A convex lens has a divergent action and a concave lens has a convergent action.

1. False
2. True

Q. Which of the following is an appropriate condition for a thin lens?

1. Aperture << Radius of curvature
2. Aperture >> Radius of curvature
3. Aperture = Radius of curvature
4. Aperture is more than the focal length.

Q.

If light source is at focus of concave lens, then after refraction the ray of light will ____________.

1. will never be parallel to principal axis

2. will converge at the centre of curvature.

3. be reflected back.

4. parallel to principal axis

Q. Define the following term:
Optical center

Q.

A lens which is thinner at its centre than at its edges is called ___.

1. concave lens

2. convex lens

3. plano-convex lens

4. plano-concave lens